Breech mechanism for ordnance.



G. L. SMITH & D. F. ASBURY. BREBGH MECHANISM FDR ORDNANGB. APPLICATIONFILED MAY 31, 1911.

Patented Mar. 19, 1912.

12 SHEETS-H1231 1.

G. L. SMITH & D. F. ASBURY. BREEGH MECHANISM FOR ORDNANGE.

APPLIUATION FILED MAY 31, 1911. 1,020,849. Patented Mar. 19, 1912.

12 SHEETS-S HEET 2. s

G. L. SMITH & D. P. ASBURY. BRBEGH MECHANISM FOR ORDNANCE. APPLICATIONFILED MAY 31, 1911. 1 ,020,849 Patented Mar. 19, 1912.

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G. L. SMITH & D. P. ASBURY. BREEGH MECHANISM FOR. ORDNANOB.

APPLIOATIOH FILED MAY 31. N11. 1,020,849. Patented Mar. 19, 1912.

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BREBCH MECHANISM FOR ORDINANCE.

APPLICATION FILED MAY 31, 1911.

Patented Mar. 19, 1912.

12 SHEETS SHFET D anuemtozs G. L. SMITH & D. P. ASBURY. BREEOH MECHANISMFOR ORDNANOE.

APPLICATION FILED MAY-31, 1911.

1,020,849. Patented Mar. 19, 1912.

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BREEGH MECHANISM FOR ORDNANGE.

APPLIGATIOH TILED MAY 31, 1911 Patented Mar. 19, 1912.

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G. L. SMITH & D. F. ASBURY. BREEOH MECHANISM FOR ORDNANDE.

APPLIUATIOH FILED MAY 31, 1911. 1,020,849. Patented Mar. 19, 1912.

12 SHEETBSHEET a.

G. L. SMITH & D. F. ASBURY. BREEOH MECHANISM FOR OEDNANGB.

APPLICIATIDN FILED MAY 111111 1.

. Patented Mar. 19, 1912.

G. L. SMITH & D. F. ASBURY. BRBECH MECHANISM FOR 03111111105.

APPLICATION FILED MAYSI, 1911.

1,020,849. latented Mar. 19, 1912.

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APPLICATION FILED MAY 31, 1911. 1 20,849. Patented Mar. 19, 1912.

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\ APPLIGATION FILED MAY 31, 1911. 1 ,O2Q,849 Patented Mar. 19, 1912. 12BHEETS'SHEET 12.

UNITED STATES PATEN T OFFICE.

GEORGE L. SMITH AND DORSEY IE. ASBURY, OF WASHINGTON, DISTRICT OFCOLUMBIA.

BREECH MECHANISM FOR ORDNANOE.

To all 'tU/ZOYM it may concern.

lie it known that we, (inouor: In SMITH and Donsnr l. Asnunr, citizensof the United States. residing at Washington, District of Columbia, haveinvented certain new and useful 1m provenn-nts in Breech Mechanism forOrdnance; and we do hereby declare the folloi'ving to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it amn-rtains to make and use the san'ie.

Our invention relates to the construction of breech mechanism tor guns,and is particularly designed to afford a simple. durable and etiicientmechanism oi this character for guns using ammunition which is too heavyor cumbersome to be loaded automatically.

The principal objects of the invention are to obtain rapidity ofoperation; to reduce loss of power due to overcoming the weight, inertiaand friction of moving parts; to provide a mechanism which will make itunnecessary for the operator to at any time stand in the path of therecoil of the gun; to sim plify and reduce the number of parts and tomake each part of such a form as to be suitable for either right or lefthanded mounts; to utilize the energy stored up in the mechanism whileswinging it into the breech to initiate a locking rotation of the plugupon its axis, thus eliminating the slamming action of the plug after ithas entered the gun breech and before it starts to rotate, andconsequently increasing the rapidity with which it is possibleto'opcrate the mechanism and also relieving both the gun and operatorfrom unnecessary strain; to provide means for securely locking the pinagainst rotation when the gun is fired without the use of so-called plugand carrier latches, which, as is well known, are more or lesssusceptible to derangement; to provide simple and eflective meanswhereby the operator may easily control the plug as it swings out of thebreech end of the gun notwithstanding that the ship upon which it may bemounted may be rolling or pitching heavily; to avoid the use of gearwheels in applying power; to reduce as far as possible the clearancecuts in the threads of the plug and screwbox necessary to permit theplug to swing upon its hinge; to provide a magazine firing lock whichoperates to place the primer after the breech is closed and almostcompletely locked and which may be oper- Specification of LettersPatent. Application filed May 31, 1911.

ting the rapid ejection of Patented Mar. 19, 1912. Serial No. 630.351.

oi the gun where the the recoil, thus permita primer which has failedand the insertion of another prnner In order that a further attempt tofire the gun may be quickly made; to provide for the automatic loadingof primers;

to prevent the wedge of the lock from crushmg the primer in case theprimer jams in loading; and to provide for exploding the primer not onlyelectrically but by percussion when the operator is at a distant pointas well as when he occupies a position at the side of the breechmechanism.

Generally stated, the breech mechanism by which the be. ore notedobjects of our invention are accomplished is of the carrier type andcomprises a hinged carrier upon which is rotatably mounte d a breechplug that is provided with interrupted threads and is rotated axially bymeans of a crank which is also mounted on the carrier and which isoperated through the instrumentality of a lever that additionally servesas a means for swinging the there being likewise carrier upon its hingepin, mounted upon the carrier a magazine firing lock which may beoperated from the side of the gun and which is so related to the otherparts of the mocha nism that the prime r is not loaded until the breechplug is substantially in locked position, the said crank and breech plugbeing operativcly so combined that the former effectively resists anytendency of the plug to perform an unlocking rotation such as mightresult from internal pressures when the gun is fired, and the breechplug and a portion of the gun provided with adjacent theretofbeingcotiperating cam devices whereby the plug is caused to rotate upon itsaxis through a small angle as it swings about the hinge pin of thecarrier when in proximity to and a from its closed struction embodies tour invention. 1

pproaching or receding position; and such a conhe principal features ofIn the drawings chosen for the purpose of illustrating our invention,the scope whereof is pointed out in the claims, Figure 1 is an endelevation of a gun provided with breech mechanism ance with ourinvention,

constructed in accordthe parts being shown in the positions they occupywhen the gun is ready to fire,

Fig. 2 1s a view,

partly in plan and artly in horizontal central section, of the reechmechanism ill ustrated in Fig. 1, the parts being shown in the relativepositions they occupy when the gun is ready to fire; Fig. 3 is a view,partly in plan and partly in horizontal central section, showing thebreech mechanism when swung open ready for loading; Fig. 4 is a. detail\iew, partly in plan and partly in horizontal central section, showingthe breech plug operating devices and the magazine firing lock, theparts being shown in full lines in the positions they occupy when thegun is ready to fire, and the cocked position of the hammer, firing pin,firing trigger and connecting parts being shown in dotted lines; Fig. 5is a view of the breech mechanism, partly in side elevation and partlyin vertical section, the parts being in the positions illustrated inFigs. 1, E2 and i; Fig. 6 is a detail view, partly in plan and partly inhorizontal section on the line G t], Fig. 7, showing the magazine firinglock, the positions which the parts occupy when the gun is ready to tirebeing illustrated in full lines and the positions assumed by the partswhen the breech is swung open being shown in dotted lines; Fig. 7 is adetail elevation of the I)Ol' tion of the mechanism illustrated in Fig.(3', Fig. 8 is a detail view, partly in plan and partly in horizontalsection on the line 88, Fig. 9, showing the magazine firing lockoperating mechanism, the positions which the parts occupy when in theready to tire position being shown in full lines and the positionsassumed by the parts when the operator handle -is actuated to eject aprimer which has failed being shown in dotted lines: Fig. 9 is a detailelevation of the parts illustrated in Fig. 8', Fig. 10 is a detail viewtaken in the plane of the line 10 M), Fig. l, the crank by which thebreech plug is rotated being shown in elevation, the relation of theoperating parts to the breech plug when the latter in locked positionbeing shown in full lines and the positirms assumed by the parts whenthe plug is rotated to unlocked. position being illustrated in dottedlines; Fig. 11. is a detail view taken in the plane of the line ll il,Fig. it], showing in full lines the relative positions of the parts whenthe breech plug is in locked position and showing in dotted lines thepositions which these parts occupy when the plug has been rutated tounlocked position; Fig. 12 is a detail elevation of the threaded breechplug and screw box, together with the cam devices by which the former isrotated upon its axis to prevent slanuning, the relation of the plug andscrew box when the plug has completed its unlocking axial rotation beingillustrated in dotted lines and the relation of the plug and screw boxat the beginning of the engagement of their threat is being illustratedin full lines; Fig. 13 is 21 detail section of the cam devices taken inthe plane of the line llll3, Fig. 12,, the

dotted posi ion of the cam roller corresponding to the dotted positionof the breech plug in Fig. 12; Fig. 14: is a detail elevation of theportion of the breech plug which cooperates with the control are; Fig.15 is a detail view taken in the plane of the line .15-15, Fig. 3,showing the relation of the breech plug and control are; Fig it is adetail view, partly in plan and partly in horizontal section, showingthe relation of the control are and breech plug when the latter islatched or locked in open position; Fig. 17 is a detail view, partly inplan and partly in horizontal section showing the fluid pressureactuated devices for cooking the firing mechanism and releasing the mainspring thereof; Fig. 18 is a detail sectional view, ta hen in the planeof the line l8 -1S, Fig. 8; Fig. 19 is a detail sectional view, taken inthe plane of the line 19--l9, Fig. 8; Fig. 20 is a. detail frontelevation of the operator bar of the tiring mechanism; Fig. 21 is a.detail plan view of the operator bar of the tiring mechanism; Fig. 22 isa detail horizontal central section of the receiver member of the tiringmechanism, Fig. 23 is a detail elevation of a. portion of the liringmeclninism, showing the relation of the receiver and primer extractor;Fig. 2 1 is a detail vertical section of the receiver, lock wedge,primer extractor and the end of the mushroom stem, the parts being shownin the position illustrated in full lines in Fig. 6; Fig. 25 is a detailplan view of the magazine and wedge; Fig. 26 is a detail elevation ofthe devices i lustrated in Fig. 25; Fig. .3? is a detail verticalsection, taken in the plane of the line BT 27, Fig. (5, show ing therelation of the hannner to the wedge and receiver of the liringmechanism; Fig. is a. detail plan view of the magazine loch, showing theparts in position for feeding the primer from the n'nigazinc to theprimer chamber in the end of the mushromn stem; Fig. EU is a detailsectional view taken in the plane of the line EFL-25), Fig. '1, showingthe lowermost primer in the magazine unlatched and also showing thehammer unlatched and ready to t'orce the primer into the primer chamberof the mushroom stem; Fig. 30 is a detail end elevation of the magazine;Fig. 31 is a detail cctional view of the magazine, taken in the plane ofthe line lll ill, Fig. 2f); Fig. 232 is a detail horizontal section ofthe magazine, taken in the plane of the line 3QZll, Fig. 29; Fig. 33 isdetail view of the resilient. primer guide; Fig. Illis an end view ofthe primer guide shown in Fig. 33; Fig. 33 a detail side elevationshowing the relation of the operating lever and the safety jaws when thebrew h plug has been rotated upon its axis to unlcrlied position; Fig.36 is a countersunk, as

detail end elevation of the safety jaws shown in Fig. 35; Fig. 37 is adetail horizontal section taken in the plane of the line 37-417, Fig.Fig. 38 is a detail elevation of a portion of the screw box, showing oneof the extended threads at the outer end thereof; and Fig. 39 is adetail section taken in the plane of the linc' ac -3a. F ig. 12.

In the drawings, 1 is the screw box liner, 2 the breech plug and 3 thecarrier. The screw box liner 1.; which, as more particularly showninFigs. 2, 3 and 4, is screwed into the breech end of the gun, is providedupon one side with perforated hinge lugs 4 which are adapted to receivea hinge pin 5 by means of which the carrier 3 is pivotally mounted uponthe gun. These hinge lugs 4 which may be conveniently recessed into thescrew box liner 1 and rigidly secured thereto by means of a screw bolt4;, are preferably located close to the side of the gun so that thebreech plug mounted upon the carrier 3 shall be required to swingthrough a short are only and shall overhang or project outwardly fromthe gun but a short distance when the breech is open, the resistancewhich the weight, inertia and friction of parts ofi'er to the swingingof the carrier 3 upon its hinge pin being thus reduced. In order todecrease the bearing pressure on the hinge lugs 4 said lugs, as shown,are preferably separated as widely as possible so as to aflord a largesupporting leverage for the carrier 8 and associated parts. As shownmore particularly in Fig. 5. the hinge pin 5, which is preferablyrigidly secured to the carrier by means of a key 5* that fits intocorresponding liey-ways formed in. the hinge pin and carrier, may beconveniently secured in the hinge lugs l by means of a nut 5 which hasthreaded engagement with the reduced lower end of the hinge pin, theupper end of said hinge pin being headed as at 5. For the purpose ofbeing readily able to compensate for wear a washer 5 is preferablyinterposed between the lower hinge lug 4 and the carrier 3, the adjacenthinge lug of the carrier being recessed or shown, to receive such asher.lVhen, as illustrated in the drawings the parts are assembled as a righthanded mechanism, the corresponding washer-receiving recess in the upperhinge lug of the carrier 3 forms an oil space 5". When the gun isconverted intoa left handed mechanism the carrier 3 is reversed inposition and the supporting washer 5 is trans ferred to thewasher-receiving recess of the other carrier hinge lug, which thenbecomes the lower hinge lug, as will be readily understood. If desired,the hinge pin 5 may be provided with oil grooves 5'.

The carr 2r may be conveniently fashioned asa yoke or frame member 3which is provided at one end with a plurality of perforated hinge lugs 3that. are adapted to receive the hinge pin as heretofore described. Theinner end of the carrier is formed with an inwardly projecting boss orhollow spindle upon which the breech plug 2 is rotatably mounted, saidspindle being rovided at its inner end with a cylindrical liearingportion 3 which is adapted to enter a corresponding recess formed in thebreech plug approximately at its center of gravity, and being alsoprovided with threads 3 which engage corresponding threads cut in therear end of the plug and thus securely maintain the plug upon thecarrier. The threads 3. which are of the threads of the breech plug 2,permit the latter to travel forwardly into the gun in t locking to thuscompress the gas check pad while the carrier 3 remains at rest with Hrespect to the screw box 1. The breech plug 2. which s preferably of lthe Welin or stopped thread type, is. generl ally speaking. of the usualdesign, but the blanks 2 thereof are made somewhat wider than the steps2 so that upon an unlocking rotation of the plug the threads thereon aredisengaged from those in the screw box liner lbefore the plug hasrotated through the angle subtended by the blank, thus permitting theplug to swing around the hinge pin of the carrier while simultaneouslyrotating upon its own In the particular construction illustrated in thedrawings. the breech plug 2 rotates upon its axis through an angle ofapproximately twenty-seven and a half degrees, which is an angularrotation of about five t degrees more than is necessary to disengage Ithe plug and screw box threads. This additional rotation of the plugserves to aiTord l clearance between the right hand ends of the lstepped rows of threads on the plug and the i left hand ends of thecorrespondingly stepped t rows of threads on the screw box 1 so that thebreech plug may swing outwardly without the necessity of providingclearance cuts l except at the back ends 1 and 53 of the highest stepson the screw boxgind breech plug, respectively. The additional axialrotaticn which the breech plug 2 is permitted to have over and abovethat required to disengage its threads from those of the screw box 1also permits the employment of cam devices by means of which themomentum of the plug and carrier, as they swing around the hinge pin 5,may be utilized to prevent theslamming of the plug. thus eliminating thepossibility of it. rebounding from the screw box as the breech isclosed. To this end the breech plug 2 is provided with a cam roller 2"which is journaled upon a headed pin 2*" that, as shown in Flg. 1, maybe conveniently maintained m an appropriate socketm the plug by mcanwi ascrew,2,

the same pitch as the breech plug 2 upon its axis for the purwhile thescrew box liner 1 is formed with an adjacent cooperating cam surface 1'the pitch of which. as more particularly shown in Fig. 13, is such thatat the end of the swinging movement of the breech mechanism on the hingepin the motion of the breech plug 2 is ronrerted from a simple swingingmovement on the hinge pin into an advancing axial rotation correspondingto the pitch of the threads upon the breech plug and screw box. the plugat the end of the coitperation of the cam face 1 and cant roller 2 beingthus accurately delivered to the extended threads 1 at the forward endof the screw box which guide or lead the plug threads so that theyproperly engage those of the screw box 1. Similarly, when the operatinglever 7 is actuated to rotate pose of disengaging its threads from tho con the screw box 1, the momentum of the plug. acting through the camsurface 1" and cooperating cam roller 2, is utilized to force the breechmechanism away from the screw box 1 and to initiate its swingingmovement on the hinge pin 53, it being thus possible to rapidly actuatethe operating lever T without danger of it. being suddenly arrested.

ln order to prevent the plug 2 from rotating while open and to maintainit in a position which will permit it to properly enter the screw box '1when swinging to closed position. as well as for the purpose of enablingthe operator to control the plug in case it starts to swing accidentallywhen the ship is rolling hearily, it is preferred, in case of very largeguns, to employ a horizontally extending con rol are H the center ofcurraline of which corresponds to the axis of the hinge pin 5, saidcontrol are being preterahly secured to the screw box liner 1 by means,of screws t and its upptr surface being adaptcth upon a slight rotationof the breech plug 3 upon its axis, to engage the surface 2 between twosteps of the plug threads to thus operate as a friction hraltc which maybe called into action at the will of the operator by simply rotating theop crating lercr T through. a small angle, as will be readilyunderstood. hen a core trol are or hralomember such as l3 is emlltlyttl. the breech plug 2 is also preferably formed with an inclinedshoulder i against which the outer end ft of the control are is adaptedto abut when the operating lever T is lifted slightly after the breechplug has been swung to fully open position, the plug being thus latchedagainst swinging to closed position until the operating lever issubsequently lowered. The inner end (3 of the control are arts as theinverse side of the cam surface 1" shown in Fig. 13, operating inconjunction with the outer end of I he surface of the plug and. theadjacent portion of the outer face of the plug thread 2 The rotation ofthe breech plug 2 upon its axis and the swinging of the entire breechmechanism on the hinge pin 5 are both effected through theinstrimieutality of a single operating lever 7 which is pivotallymounted upon the carrier at the side thereof and between the hinge lugs3. This operating lever is rigidly connected to a plug actuating crankshaft 8 which is journaled on the carrier 3, the inner journal bearing 3of the shaft being preferably detachable and connected to the carrier bymeans of threaded bolts 3 which connect the operator bar hearing 25 tothe carrier, and theoutcr journal bearing, 3*, being formed in thecarrier. The cylindrical crank pin 8 at the inner end of the crank shaft8 enters a corresponding recess in a cylindrical crosshead t) which isslid-ably and rotatably mounted in an appro priate cylindrical guidingrecess 10 formed in a crosshead bearing member 10 that is rig idlysecured to the breech plug 2 by means of a threaded bolt It) and lockscrews 10", the said bearing member 10 being also preferably providedwith an inwardly project'- ing lug or flange 10' which fits into acorresponding recess formed in the face of the breech plug 2 to thusmaintain the bearing member 10 in proper position and at the same timerelieve its securing bolts 10" and 10 of strain. The crosshcad guidingrecess 10* is made of sutlicicnt length to permit the crank shaft 8 tobe rotated through the required angle in either direction from the deadcenter position, which is the position illustrated in Fig. ll, themechanism being thus capable of use in either right or left handedmounts for, as will be readily understood, a rotation of the crank shaft8 in either direction will cause the slidable crosshcad 9 and crossheadbearing 10 to always rotate the breech plug E5 in an unlockingdirection. it may be here noted that the crank shaft 8, by reason of itbeing on dead center when the breech mechanism is fully closed, locksthe breech plug 2 against an accidental unlocking rotation, and it willbe also noted that: as the crank shaft is at its dead center positionwhen the gun is tired, but little effort is required to loosen the gascheck pad aft r tiring, for it Your small force applied to the operatinglever T will produce an enormously increased force acting through thecrank shaft 8, crosshead 9 and crosshead bearing 10 to effect anunlocking rotation of the breech plug. The crosshead bearing member 10is also provided with an outwardly projecting detent 10* having aninclined or beveled face it), such detcnt servin; to control theoperation of the inaga, zine wedge, as will hereinafter appear, tothereby prevent the possibility of closing the tiring mechanism andexploding the primer before the breech plug 2 has been rotated to itslocked position. and the inclined face serving to cause the magazinewedge to be withdrawn to a safe position as the breech plug 2 rotates toits unlocked position in case any part of the tiring mechanism 18 brokenor for any other cause fails to act.

The operating lever 7 is preferably rigidly connected to the plugoperating crank shaft 8 in the following manner. The lever cam 11 bywhich the firing mechanism is normally operated is provided with ahollow cylindrical sleeve 11' which is journaled 1n the bearing 3'ceives the outer end of the crank shaft 8, the latter being securedthereto by means of keys 11 and a bolt 11 which passes through thecenter ofthe lever cam and has threaded engagement with the shaft. Theouter face of the lever cam is provided with a. threaded boss 11 whichengages the correspondingly threaded portion 7 of the operating lever 7,keys 7" being employed for the purpose of preventing the lever fromunscrewing.

In order to arrest the unlocking rotation of the breech plug 2 when ithas turned upon its axis through the required angle, the lever cam 11 ispreferably provided with stops or projections 11 which are adapted toengage corresponding stops 'or abutnients 3* with which the hingedcarrier 3 is provided, the stops ll and'3 being arranged to cooperate inpairs, one pair being operative when the mechanism is assembled for aright handed mount and the other pair beingsimilarly adapted to engagewhen the n'iechanism is assembled for a left handed mount; and in orderto limit the locking rotation of the plug upon its axis, the operatinglever 7 maybe conveniently arranged to come into contactand be arrestedby a fixed portion of the gun after having rotated the crank shaft 8through the necessary angle, the operatiii'g lever 7 being for t ispurpose preferably fashioned with a projecting stop 7 which is adaptedto engage the rear face of the gun yoke 12. as more particularly shownin Fig.

As the control are 6, which, as heretofore described. serves to preventthe breech plug 2 from rotating while swinging to open position, isordinarily used only on very large guns where itis desirable to preventthe plug from swinging too rapidly and also to latch it in open positionso as to prevent it from swinging inwardly when the ship rolls, it ispreferred to form the operating lever T with an arm or extension 7'that, when the breech mechanism is swung upon the lingo pin 5. isadapted to pass between are shaped parallel safety jaws or stops 13'that are preferably formed as an integral bracket wl-ich is secured tothe gun yoke 12 between the hinge lugs 4 by means of screws 13. As willbe seen upon reference to Figs.

of thecarrier and which re l l l and 37, before the breech mechanism canbe swung to open position on the hinge pin 5 the operating lever T bywhich the rota.- tion of the breech plug 2 is effected must be turnedthrough an angle sufficient to cause the outer end of its extension 7 toassume a position which will permit it to pass above the upper surfaceof the proximate safety jaw 13. W'hen, shown in Fig. 35, the operatinglever T has been turned to completely unlock the breech plug 2, thebreech mechanism may be swung upon the hinge pin 5 by pulling outwardlyupon the operating lever, the outer end of the extension 7 of the latterpassing above the lower safety jaw 13 and thus preventing the operatorfrom rotating the plug upon its axis toward locked position until afterthe carrier has been properly swung around the hinge pin 5 toward closedposition. 'hen a control are 6 is employed in conjunction with thesafety jaws l3 and the extension 7" of the operating lever, the innerends of the safety jaws are somewhat depressed or hollowed out, as at13". in order to permit the operating lever 7 to rotate slightly afterits extension 7 has passed between the safety jaws, thus permitting thebreech plug 2 to be forced into frictional engagement with the controlare 6 and to latch the plug in open position, as heretofore described.the mechanism is assembled in the drawings the lower safety jaw 13eoiipe ates with the extension i of the operating lever; but the uppersafety jaw 13 similarly cooperates with the extension of the operatinglever when the mechanism is assembled as a left handed mount. For smallguns. it is preferred to omit the control are (3 and to employ thesafety jaws l3 alone, as the latter are more accessible, simple inconstruction, and necessitate no cuts either in the plug 2 or screw box1.

The mushroom 14, which is provided with the usual form of head 14- forn'iaintaining the gas check pad 15 in proper position with respect tothe inner face of the breech plug "3, is mounted upon the carrier 3 soas to be capable of sliding but incapable of rotating with respectthereto, the mushroom stem 14', which is received by the hollow spindle3" of the carrier, being for thispurpose connected to said spindle bymeans of a key 14 that enters a longitudinally extending keyway in themushroom stem. The rear end of the mushroom stem is formed with 'theusual primer seat 14 (see Figs. 6, 24 and 28) and with the well knownflash passage 14 which extends through the mushroom stem and head andpermits the fire from the primer to pass into the ammunition chamber ofthe gun. In order that the mushroom head 14" may compress the gas checkpad 15 the requisite amount, the bore in thefouter end of the spindle 3of the carrier is enlarged to lOO form a chamber which receives a spring14 that encircles the mushroom stem and is maintained thereon by meansof a nut 14 of the usual design, a hardened steel washer 14* beinginterposed between the inner end of the spring and the spindle 3".

The receiver member 16 of the firing mechanism is detachably mountedupon the mushroom 14, the stem 1 t of the latter being preferablyprovided with interrupted annular collars 14 which are adapted to fitinto corresponding are shaped grooves between similar interruptedcollars 16 formed on the interior of the boss or thimble 16 of thereceiver, the interrupted collars 14 and 16 being of such length that byrotating the receiver 16 on the mushroom stem 14 through an angle ofninety degrees the collars will be disengaged and the receiver may bedetached from the mushroom stem. When in operative position the receiver16 is maintained against accidental rotation by being interposed betweena fixed stop and a movable stop, the former, 3, being rigidly connectedto and projecting outwardly from the face of the carrier 8, and thelatter, 3, being preferably formed as a pin or button which is socketedin the carrier 3 and normally maintained in projected position by meansof a small spiral spring 3 The inner face of the recelver 16 is formedwith a recess 16 which is adapted to receive and permit the oscillationof an extractor 17 by means of which the primers are extracted from theprimer seat of the mushroom stem 14". The end of the extractor 17 whichis adjacent to the mushroom stem is bifurcated to form arallel fingersli' which, as more particular y shown in Fig. 24, are ada ted to fitinto a slot or recess formed in tlie outer end of the mushroom stem andto extend upon opposite sides of and form a movable base for the primerseat 14 therein. The opposite end of the extractor is provided withoutwardly projecting curved cam fingers 17 which are adapted to extendinto corresponding grooves or cam slots 18 formed in the sliding wedge18 of the lock mechanism. Intermediate of its ends the extractor 17 isfashioned with oppositely extending pintle's 17 which are adapted tooscillate in elon ated bearings 16 of the receiver 16, such earingsbeing conveniently formed, as shown, by drilling through the receiver'from top to bottom a hole 16 of elbngated or oblong crosssection. Inthe operation of opening the breech mechanism, when the wedge 18, whichis slidably mounted upon the receiver, has been withdrawn sufficientlyfar to bring the shallowi'ng bottoms at'the inner ends of .its camgrooves 18 oppositethe outer ends of the cam fingers 17", the curvedfaces of the lat ter roll upon the adjadent fiat face of the receiverrecess 16 andthe extractor 17 is rotated or rocked outwardly to theposition shown in dotted lines in Fig. 6, thus operating to extract theprimer.

The upper and lower walls of the receiver between which the wedge 18reciprocates are provided on their inner faces with oppositely extendingflanges 16 which serve to maintain the wedge in operative position withrespect to the receiver and to guide it during its movement with respectto the latter. The upper and lower faces of the receiver are alsoprovided with symmetrically disposed cam slots 16 one of which, as willhereinafter appear, is designed to control the operation of the combinedmagazine bottom and hammer latch when the mechanism is assembled for aright handed mount and the other of which is designed to similarlycontrol such device when the mechanism is assembled for a left handedmount.

In order to permit the wedge 18 upon which the magazine is mounted toremain stationary and in proper position while the hammer 20 is feedinga primer, as well as for the purpose, as will hereinafter appear, ofthrowing the devices out of operation so as to prevent breaking of anyparts should the primer become jammed, therear ends of the upper andlower faces of the receiver 16 are formed with curved stops or abutments16 which are adapted to engage correspondingly curved stops 20 formed onthe hammer and thereby prevent inward movement of the wedge 18 untilafterthe hammer stops 20 have moved out of engagement with the abutments16 at the completion of the rotary movement by which the hammer 20 feedsthe primer from the magazine to the primer seat 14 of the mushroom stem14*. The outer faces of the upper and lower walls of the receiver arealso preferably provided with vertically extending recesses 16 which areadapted to receive correspondingly formed lugs 20 with which the hammer20 may be provided, said lugs 20" being designed to bear against andslide upon the outer vertical faces 16 of the cheeks of the receiver asthe mechanism is closed, thus preventing full contact of the point ofthe firing pin 21 with the primer until the wedge 18 has traveled to itsclosed position, at which time the hammer supporting lugs 20 registerwith the recesses 16 of the receiver. As more particularly shown inFigs. 6 and 22 the recess 16 of the receiver and the corresponding lugs20 of the hammer are preferably formed with mating inclined faces whichco-act upon the o ening of the breech to lift the firing pm 21 and thusprevent it dragging across the primer.

In order to rotate the hammer 20 outwardly when the wedge 18 iswithdrawn, the receiver 16 is provided with a vertically extending camlug or abutment the inner face and rear corner 16 whereof are adapted toarrest the cam finger of the hammer and cause the hammer 20 to pin 20until it i the end of the is supported by the vertical face 16" of thereceiver lug, the hammer 20 being thus retained in the raised positionshown in dotted lines in Fig. 6. To provide clearance for the hammerstops 20* sutficient to permit the hammer 20 to he raised of the mainspring 29 when tl to be fired by percussion. and means whereby the hammeposition when the wedge is be lowered, as well trolling the raising ofthe hammer so that it cannot be fully raised to the position shown indotted lines wedge 18 has reached a position where, as shown in fulllines in Fig. 6, the firing pin aperture 18 thereof is in properalinement with the primer to permit the firing pin 21 to explode thesame, all as will presently ap pear, the upper and lower walls or cheeksof the receiver 16 are formed with parallel s turned to a position where1e primer; is also to provide r, if in raised withdrawn, shall slots 16afl'ording inclined faces 16" that are 7 adapted to cngagethecorrespondingly inclined inter faces of the hammer stops 20 to limit therotation of the hammer 20 upon its pivot pin 20. By thus hunting therota- ;ion of the hammer 20 the movement of the arimer feeding prong 20thereof is also :ontrolled and the latter is prevented from vithdrawingfrom the magazine 19 sutliiien'tly far to allow a fresh primer to fallnto a position where it may be fed to the irimer seat until the wedge 18has actuated he extractor 17 to cause the previously fed rimer to beextracted.

The movement of the wedge 18 toward fir- 1g position is limited by theengagement of 1e stop face or shoulder 16" of the receiver 'ith thecorn-sponding 3 ot the wedge, as w ood. The wedge 19. which is providedwith outill -be readily underardlv projecting perforated lugs 18 bevccnwhich the hammer ounted by means of the pi ith a recess of aperture 18receive the firing pi ntaot the end of th 90 is pivotally n 20. isformed that is adapted n 21 and permit itto e primer 22 when the algohas'traveled to its closed position. more particularly shown in Fig. 6.Near 1 inner end the wedge is formed with a. ping or inclined face 18which, if the imer 22 he not fully entered in the primer it l i of themushroom stem. serves. near 2 end of the locking movement of the dge 18.to engage the' end of the primer 1 force it inwardly to proper position.

i l l For the purpose of permitting the wedge to be positively withdrawnby the operrotate upon the cam finger slides over and against the actionas for the purpose of conin Fig. t until the.

stop shoulder or lug moved to open position. the wedge is preferablyformed with an extension having an upwardly projecting lug 15 whichenters a correspondingly formed recess :23 with which the operator baris provided: at its I ge 18 i ator bar 93 when the breech mechanism isinner end. The extension ot' the wcd is also preferably fashioned withan inwardly projecting lug haiing an inclined face 18 which is adaptedto be engaged by l the correspondingly inclined face 10 of the i detentcarried lrv the crosshcad hearing 10. 1' Until the breech plug 2 hasrotated toward l l l l lOckEtl position sniliciently tar to permit thelug last mentioned to escape from the detent 10 ot' the crossheadhearing. the wedge 18 ing to a position in explode the firing mech anismshould he broken or from any cause i should fail to act when theoperating lever l 7 is manipulated to open the breech. the inisprevented from inov which the firing pm '21 can primer. In ase an; partof the clined face 10 at the end of the dctent 10 engages theeorrespeindingly inclined face 18' of the wedge and causcs the latter toi be withdrawn to a safe position in which the I firing pin 21 is clearof the primer.

5 The magazine 19, which is preferably {symmetrical above and below theprimer guide recess 19 through which the primers l 22 pass to the primerseat li in the mushroom stem. is

mounted upon the wedge 18, being prefe rabl v ii'itegrallv unitedthereto. Inorder to permit the feeding prong 2050f the hammer 20 to moreinwardl and force a primer from the magazine into the primer seat, themagazine is open at its front end, as at 19 and its side adjacent to thefeeding finger of the hammer is slotted horizontally, as at 19. Thehorizontally slotted side of the magazine 19 is also preferably formedwith a vertically extending slot 1:) which enables the operator toinsert his finger into the magazine and readily withdraw the primerstherefrom wh never desired. T he magazine bottom 19*, which also servesas a latch prong 20 of the hamto prevent the feeding the magazine untilthe mer :20 from entering latter is in proper alinement with the primerseat 14" in the mushroom stem, as will hereafter appear. is pivotallymounted upon the bod of the magazine by means of a pin 19. which isadapted to he received by one or the other of the pivot pin openings l9that are formed in the magazine body above and below the primer-guiderecess 1!). the pivot pin 1!) being designed to enter one of the pivotpin openings 19 when the magazine is assembled as a right handed mountand to enter the other pivot pin opening when the magazine is assembledas a left handed mount. Mounted upon the magazine bottom or hammer latch19* is a spring 19 the outer end of which, as shown in Figs. 29 and 30.bears upon the body porti n of the magazine 130 quitting a primer to beforced thcrefro 19 to thus normally maintain the movable magazine bottom19 in the elevated position illustrated in Fig. 29 by dotted lines, thisposition being that in which the feeding finger 90 of the hammer 20 islatched against executing a primer feeding move ment. At its inner endthe magazine bottom, which is preferably of hell crank form, is providedwith. a cam finger or stud 19 that extends into the adjacent slot 16 ofthe receiver 16, each of said slots 16 being'provided on its workingside with an inclined face or shoulder 16' which, when the wedge 18 andattached magazine 19 slide on the receiver 16 toward locking position,serves to act upon'the cam stud 19 and cause the magazine bottom 19 torotate upon its pivot pin until it assumes the lowered positionillustrated in Fig. 29 in full lines, the upturned outer end of themagazine bottom being thus Withdrawn from the path of the feeding prong20 of the hammer and the latter being permitted to perform its functionof feeding one of the primers from the magazine. The sloping faces orinclines 16' are so located that the magazine bottom 19 is withdrawnfrom the path of the feeding prong of the hammer 20 at the instant themagazine is in propenposition for erto the primer seat 14 in themushroom stem.

' In order to prevent forward movement of the primers '22 until theproper time. the inner faces of the rear end of the magazine body areprovided with oppositely disposed vertically extending guide grooves 1S)which receive the nibs or flanges of the primers and prevent forwardmovement of the primers until'they are in alinement with the opening.

19 in the magazinea An are shaped groove 1!), corresponding to thecurvature of the primer flange, is formed in the upper face of thehammer latch or magazine bottom 19 at the outer end thereof, such curvedgroove serving, when the hammer latch is in elevated position, toreceive the lower portion of the flange of the primer 22 which is to befed, thus preventing the primer from moving forward until the hammerlatch of the magazine bottom 19* has been lowered to release the feedingprong 20' of the hammer, even though the primer be free from the guidegrooves 19 and in alinement with the central opening'lti of themagazine. \Vhen the magazine bottom or hammer latch 19 move'sdownwardly, the primer released therefrom is prevented from falling bythe spring 19* which extends under said primer and supports the same. Toprevent the pos sibility of primers being e ected from the magazine bythe shock of gun fire, a spring 19", which may be riveted to the body ofthe ma zine 19 and which extends partially across t .e openings throughwhich the primers are inserted in the magazine, is

preferably employed; and, for the purpose of securing accurate alinementof the primer with its seat in the mushroom stem so as to prevent itstriking the rear face of the mushroom stem 14", a resilient primerguide 19 is employed, said primer guide being formed with a plurality ofspring fingers that are adapted to engage and guide the primer while atthe same time permitting the larger tiangedrend thereof to passtherethrough, and the fingers being preferably integrally connected to acollar which is threaded so as to screw into the correspondinglythreaded primer-guide recess 19.

In addition to the features of construction heretofore described, thehammer 20, which is pivotally mounted upon the wedge 18, is providedwith a feeding finger or prong 20 which is adapted to enter the magazine19 and feed a primer therefrom and is also provided with a plurality ofperforated pivot lugs .20 which are adapted to receive a pivot pin 20that serves to connect the hammer 20 to the spring-actuated connectingbar 24. The pivot pin 20 may be conveniently retained in position bymeans of a spring key 20* that is mounted in the lower end of the pinand extends under the lower pivot lug 520. In order that the primer maybe fired either electrically or by percussion, the firing pin :21,which, as shown, may be and preferably is of conical form, is preferablyinsulated from the hammer 20 by means of ebonite or hard rubberinsulation 21'" which surrounds the threaded stem 21 of the firing pinand extends under the flange 21 thereof. The firing pin is securelymaintained upon the hammer 20 by means of a nut 21 which also serves asa connection or terminal for the usual electric firing wire 21", thesaid nut being provided with perforated lugs which are adapted toreceive a pin 21 by which the perforated terminal sleeve 21 of thefiring wire is connected to the nut 21.

The operator bar 23, which is connected to the wedge 18, and theconnecting bar 24, which is pivotally connected to the hammer 20, areboth actuated by the cam 11 when the latter is rotated through theinstrumentality of the operating lever 7. As shown more particularly inFigs. 4, 8, 9, and 17 to 21, inclusive, the operator bar 23 is slid-ablymounted in groove or guideways 3* in the carrier 3 and correspondingrecesses formed in the inner face of the operator bar bearing 25, thelatter, as heretofore described. being secured to the carrier by means.of the bolts 3. Projecting inwardly from the inner face of the operatorbar 23 is a pairof parallel lugs 23 which are provided with elongatedslots that are adapted to receive and permit the longitu-v dinal travelof a pin 26" by which the cam actuated operator 26 is connected atitsin-

